Wireless communication devices have become smaller and more powerful in order to meet consumer needs and to improve portability and convenience. Consumers have become dependent upon wireless communication devices such as cellular telephones, personal digital assistants (PDAs), laptop computers, and the like. Consumers have come to expect reliable service, expanded areas of coverage, and increased functionality.
A wireless communication system may simultaneously support communication for user equipment (UE). UEs may alternatively be referred to as mobile stations, stations, access terminals, user terminals, terminals, subscriber units, etc. Each UE may communicate with one or more Node Bs (which may alternatively be referred to as base stations, access points, etc.) via transmissions on the uplink and the downlink. The uplink (or reverse link) refers to the communication link from the UEs to the Node Bs, and the downlink (or forward link) refers to the communication link from the Node Bs to the UEs.
Wireless communication systems may be multiple-access systems capable of supporting communication with multiple users by sharing the available system resources (e.g., bandwidth and transmit power). Examples of such multiple-access systems include code division multiple access (CDMA) systems, time division multiple access (TDMA) systems, frequency division multiple access (FDMA) systems, and orthogonal frequency division multiple access (OFDMA) systems. A Node B may assign various system resources to individual UEs that are supported by the Node B.
The present disclosure relates generally to the way in which system resources may be allocated to UEs within a wireless communication system. More specifically, the present disclosure relates to methods and apparatus for reducing the likelihood of deadlock (and in some cases, avoiding deadlock) in a wireless communication system. In this context, the term deadlock may refer to a situation where a UE has data to transmit on the uplink, but system resources are not allocated to the UE to a sufficient extent so as to permit the UE to transmit the data on the uplink.